[Coin-discuss] Wrong number of rows

[Jesper Hansen]

XPRESS version is 14.29 on Linux. I'll try to create an example.

'Jesper

On Wed, 28 Jan 2004, Matthew Saltzman wrote:

> Jesper-
> 
> What version of XPRESS are you using?  Can you send me (off-list) a small
> example problem and code that shows the issue?
> 
> Thanks.
> 
> On Wed, 28 Jan 2004, Jesper Hansen wrote:
> 
> > Hi COIN
> >
> > I'm trying to solve an IP problem with XPRESS using OSI. However when
> > calling branchAndBound the number of rows increase. Here is the code snip
> > and the output:
> >
> >     logs->out() << "Before B&B. Number of rows: " << solver->getNumRows()
> > << std::endl;
> >     solver->branchAndBound();
> >     logs->out() << "After B&B. Number of rows: " << solver->getNumRows()
> > << std::endl;
> >
> >
> > Before B&B. Number of rows: 149
> > After B&B. Number of rows: 162
> >
> > The MPS dump looks fine before the branchAndBound call, but afterwards...
> > :-(
> >
> > For instance column 310 was originally:
> >
> > C310      __OBJ___  -9993547.000   R98           1.000000
> > C310      R47           1.000000
> >
> > and after branchAndBound it is:
> > C310      __OBJ___  -9993547.000   R47           1.000000
> > C310      R98           1.000000   R154          4.000000
> >
> > Any ideas to avoid this?
> >
> > Note that solving with CLP and SBB works just fine!
> >
> >
> 
> 

-- 
Jesper Hansen, mailto:Jesper at carmenconsulting.com
Carmen Consulting, Købmagergade 53, Copenhagen K, Denmark 
Tel.: +45 33 17 91 92    Mobil: +45 61 33 29 69
http://www.carmenconsulting.com